Heeling-angle-availability-based optimal planning method of reentry corridor

Abstract

The invention discloses a heeling-angle-availability-based optimal planning method of a reentry corridor. The method comprises the following steps: firstly determining an initial reentry angle value range, determining a heeling angle area and selecting a heeling angle section; then selecting a longitudinal flight range zone and a horizontal flight range zone of an aircraft and dividing an initial reentry angle input zone; calculating longitudinal flight range deviation and horizontal flight range deviation of the aircraft when arriving at each terminal, finishing checking all the initial reentry angle input zones and all terminal zones and determining an initial reentry corridor; and finally increasing combined perturbation deviation, updating the reentry corridor and obtaining a mobility evaluation result; controlling an aircraft orbit by taking a minimum reentry angle in the evaluation result as an orbit controlling and aiming reentry angle. According to the method, the reentry corridor is designed, so the problems that the terminal state is inaccessible and the aiming point is not optimal due to a convention method of a jumping reentry aircraft can be solved; the design pressure of the reentry guidance law is relieved; the quick evaluation result can be shown to ensure that the task design is reliable and accurate.

Description

technical field [0001] The present invention relates to a re-entry corridor optimal planning method, especially a re-entry corridor optimal planning method based on roll angle availability, especially suitable for jump re-entry missions (initial speed far exceeds the first cosmic speed and range requirements), it is mainly used in the early stage of reentry vehicle mission design and guidance law design. Background technique [0002] During the reentry process of the reentry vehicle, the maximum deceleration overload, duration, and heat flow generated must be kept within a certain range. At the same time, the reentry vehicle also needs to ensure that it can land at the predetermined landing point or meet the terminal state requirements. From the perspective of engineering design experience, the flight state of the re-entry vehicle should meet certain requirements to ensure that the re-entry process can meet various constraints and ensure that the re-entry flight is safe and ...

AI Technical Summary

Problems solved by technology

Different from the re-entry vehicle whose speed is lower than the first cosmic speed, the trajectory of the jumping re-entry vehicle has a process of jumping out of the atmosphere. The effects of centrifugal force, gravity and Coriolis force cannot be ignored in the thin atmosphere. The overload and range of the flight process are affected by the previous stage, so regardless of the overload and range, the approximate solution form of the reentry motion equation cannot be used to obtain the analytical solution of the entire flight process

However, only using three-degree-of-freedom dynamics cannot evaluate the attitude-ballistic coupling caused by the ballistic instability stage exceeding the first cosmic velocity or the roll angle control in the critical stability stage of the ballistic trajectory. question

It is precisely because of the existence of this kind of problem that accurate re-entry maneuverability assessment of aircraft is also a necessary input condition for mission design and guidance law design, while traditional design methods cannot directly obtain accurate maneuverability assessment in this case result

[0004] In addition, it is well known that the re-entry process is affected by various perturbation factors, especially the perturbation of aerodynamic parameters and the atmospheric environment. Therefore, the design of the re-entry corridor must consider the influence, and cannot simply use the nominal The design of re-entry conditions is used as the basis; at the same time, there must be areas in the corridor that are less affected by perturbation, which are suitable for use as task targeting areas, which also brings the need for evaluation and optimization, which is also the traditional design method for re-entry corridors insatiable

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